Numbness, Tingling, Burning In Limbs, Weakness, Vertigo, Muscle Spasm, Tremor

Well, over the past year or so I have experienced a series of strange sensations, including numbness and tingling , pins and needles, and a burning sensation on my legs and arms. I ve also experienced periods of weakness and vertigo . Late last fall, I began to have involuntary muscle spasms in my arms, legs and face. The spasms can last from 10 minutes or persist for hours. It s not painful but it is extremely irritating. I also have experienced a light tremor in my hands that sort of comes and goes and my fingers move by themselves at times. I also have trouble walking heel to toe (shaking uncontrollably) and my feet swell on a regular basis. I am wondering if all of these symptoms are related and if so what might the cause be. I have gone to a nuerologists and gotten a series of blood tests and an EMG , but I cannot afford the MRI so I have been considering putting any other tests on the back burner until I get the finances to cover the expenses. The nueroloist has not told me if he thinks what s going on is serious but he did say that at 27 years old the symptoms that I am currently experiencing are strange and may be an indication that something is wrong with my peripheral nervous system. Is this an issue that I should address immediately or can I afford to put it off until I get better health insurance?